This type of box is being used more and more for the packing and transportation of fruit and all types of perishable products due to the fact that present technology has been progressively creating and applying new concepts of substantial simplification in shape and assembly which greatly reduce the cost of the construction of the finished package and parallel improvements in the manufacture of the raw material used, namely the corrugated cardboard.
Logically the above-mentioned improvements have been applied and used based on certain properties of strength of the corners of such boxes, a condition indispensible for stacking in which the lower boxes must support the weight of the upper boxes and of the contents thereof, for which reason there have been utilized corner pillars of high resistance to collapsing and different solutions are also being employed to avoid the sliding of such boxes when they are stacked, thereby avoiding the upper boxes dropping down sideways by sliding off from the lower boxes.
In this connection there are already known the solutions provided by Spanish Utility Model No. 266,431 of the present applicant and Spanish Utility Model No. 272,042, also of the present applicant, in accordance with which the assembled box comprises in all of its parts a single thickness of material, except at its corners where the pillars are constructed by the superimposed doubling of a series of panels which form an extension of the sides of the box and have two or three thicknesses. In these solutions, when assembling the box, there are eliminated the operations of gluing or stapling the parts of the side walls and lengthwise walls which come together at each corner, since the upper portions of the components of each pillar are connected together by fitting within a cap of plastic material of the shape of a prism with a triangular base with a lower opening to receive said parts of the pillar, this being the only manner of assembling and adjusting the pillar.